26 research outputs found
In vitro leishmanicidal, antibacterial and antitumour potential of anhydrocochlioquinone A obtained from the fungus Cochliobolus sp
The bioassay-guided fractionation of the ethyl acetate extract of the fungus Cochliobolus sp. highlighted leishmanicidal activity and allowed for anhydrocochlioquinone A (ANDC-A) isolation. MS, 1D and 2D NMR spectra of this compound were in agreement with those published in the literature. ANDC-A exhibited leishmanicidal activity with EC50value of 22.4 \uc2\ub5g/mL (44 \uce\ubcM) and, when submitted to the microdilution assay against Gram-positive and Gram-negative bacteria, showed a minimal inhibitory concentration against Staphylococcus aureus ATCC 25295 of 128 \uce\ubcg/mL (248.7 \uce\ubcM). It was also active against five human cancer cell lines, showing IC50values from 5.4 to 20.3 \uce\ubcM. ANDC-A demonstrated a differential selectivity for HL-60 (SI 5.5) and THP-1 (SI 4.3) cell lines in comparison with Vero cells and was more selective than cisplatin and doxorubicin against MCF-7 cell line in comparison with human peripheral blood mononuclear cells. ANDC-A was able to eradicate clonogenic tumour cells at concentrations of 20 and 50 \uce\ubcM and induced apoptosis in all tumour cell lines at 20 \uce\ubcM. These results suggest that ANDC-A might be used as a biochemical tool in the study of tumour cells biochemistry as well as an anticancer agent with durable effects on tumours
Deficiências após a alta medicamentosa da hanseníase: prevalência e distribuição espacial
Detection of synchronous carcinomas of the colon with F-18 fluorodeoxyglucose - A case report
Colon and rectal carcinomas are common in North America and Northwestern Europe, In South America, the risk of this disease is not as great, Adenocarcinomas are the most common types of tumors, and they occur mainly in the descending colon, sigmoid, and rectum. A patient with a possible right colon carcinoma was examined using F-18 FDG.25537037
Normal values of [Tc-99m]pertechnetate uptake and excretion fraction by major salivary glands
The assessment of the functional status of the salivary glands has been used in the scintigraphic evaluation of xerostomia. Several quantitative methods derived from standard dynamic scintigraphy have been suggested. However, the indices proposed are quite variable and unlikely to be useful in clinical practice. The objectives of this study were to obtain reference values of major salivary glands uptake and excretion fraction in healthy subjects and to obtain normal ratios of Tc-99m-pertechnetate uptake by the major salivary glands in comparison to the thyroid gland uptake. The standardization of these values has the purpose of making this evaluation faster and more objective. Fifty volunteers without clinical evidence of xerostomia or thyroid disease underwent static salivary glands scintigraphy with Tc-99m-pertechnetate. Static images were obtained at 20 minutes and then at 3 minutes after oral stimulation with lemon juice. Percent uptake, excretion fraction and salivary gland to thyroid ratio rates were calculated for the parotid and the submandibular glands. The mean of the uptake values at 20 minutes for the right and left parotid glands were respectively 0.31% and 0.26%, and for the submandibular glands 0.15%. The excretion fraction of the tracer after the lemon juice stimulation was 70% for the parotids glands, 50% for the right and 49% for the left submandibular glands. The mean +/- SD salivary gland to thyroid count ratio was 0.79 +/- 0.45 for the right parotid, 0.78 +/- 0.5 for the left parotid, 0.67 +/- 0.33 and 0.66 +/- 0.34 for the right and left submandibular glands, respectively. Salivary glands scintigraphy with uptake and excretion fraction calculation is an easy to perform, non-invasive and objective method to investigate salivary glands function. These findings help the nuclear physician to interpret salivary gland scintigraphy more objectively, even in patients with thyroid gland dysfunction in whom Tc-99m-pertechnetate thyroid uptake may be abnormal.27439540
Tc-99m-sestamibi thyroid uptake in euthyroid individuals and in patients with autoimmune thyroid disease
Purpose: We investigated the biokinetics of Tc-99m-sestamibi in the thyroid of euthyroid volunteers (EVs) and in patients with autoimmune thyroid diseases and determined the best time interval between Tc-99m-sestamibi injection and calculation of uptake. Methods: Forty EVs, 30 patients with Graves' disease (GD), 15 patients with atrophic Hashimoto's thyroiditis (AHT) and 15 patients with hypertrophic Hashimoto's thyroiditis (HHT) underwent Tc-99m-sestamibi thyroid scintigraphy. Dynamic images were acquired for 20 min, and static images were obtained 20 min, 60 min and 120 min post injection. Five-, 20-, 60- and 120-min uptake, time to maximal uptake (T-max) and T-1/2 of tracer clearance were calculated. Thyroid hormones and antibodies were measured. Tc-99m-pertechnetate uptake was investigated in GD patients. Results: T-max was approximately 5 min in all four groups. The mean T-1/2 value for EVs was similar to the GD value and lower than the HHT and AHT values. The mean (+/- SD) 5-min uptake was 0.13% (+/- 0.05%) for EVs. The 5-min uptake in GD was higher than that in EVs(P < 0.001) and correlated with free thyroxine (r=0.54) and with Tc-99m-pertechnetate uptake (r=0.68). Uptake in HHT was higher than that in AHT (P=0.0003) and EVs (P=0.002). Uptake in AHT was lower than uptake in EVs (P=0.0001). Conclusion: Five minutes is the optimal time interval between Tc-99m-sestamibi injection and calculation of thyroid uptake. Five-minute uptake differentiates euthyroid individuals from GD patients. There is a high correlation between Tc-99m-sestamibi and Tc-99m-pertechnetate uptake in GD. The reduced Tc-99m-sestamibi uptake in AHT patients is probably due to glandular destruction and fibrosis. Inflammatory infiltrate and high mitochondrial density in thyrocytes possibly explain the increased uptake in GD and HHT.32670270
F-18-Fluoride PET/CT is highly effective for excluding bone metastases even in patients with equivocal bone scintigraphy
Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Bone scintigraphy (BS) has been used extensively for many years for the diagnosis of bone metastases despite its low specificity and significant rate of equivocal lesions. F-18-Fluoride PET/CT has been proven to have a high sensitivity and specificity in the detection of malignant bone lesions, but its effectiveness in patients with inconclusive lesions on BS is not well documented. This study evaluated the ability of F-18-fluoride PET/CT to exclude bone metastases in patients with various malignant primary tumours and nonspecific findings on BS. We prospectively studied 42 patients (34-88 years of age, 26 women) with different types of tumour. All patients had BS performed for staging or restaging purposes but with inconclusive findings. All patients underwent F-18-fluoride PET/CT. All abnormalities identified on BS images were visually compared with their appearance on the PET/CT images. All the 96 inconclusive lesions found on BS images of the 42 patients were identified on PET/CT images. F-18-Fluoride PET/CT correctly excluded bone metastases in 23 patients (68 lesions). Of 19 patients (28 lesions) classified by PET/CT as having metastases, 3 (5 lesions) were finally classified as free of bone metastases on follow-up. The sensitivity, specificity, and positive and negative predictive values of F-18-fluoride PET/CT were, respectively, 100 %, 88 %, 84 % and 100 % for the identification of patients with metastases (patient analysis) and 100 %, 82 % and 100 % for the identification of metastatic lesions (lesion analysis). The factors that make BS inconclusive do not affect F-18-fluoride PET/CT which shows a high sensitivity and negative predictive value for excluding bone metastases even in patients with inconclusive conventional BS.391117301736Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)FAPESP [09/51799-3
Cr-51-EDTA measurements of the glomerular filtration rate in patients with sickle cell anaemia and minor renal damage
Background Creatinine clearance has been reported to be inaccurate for the estimation of glomerular filtration rate (GFR) in patients with sickle cell anaemia (SCA). Inulin clearance, the reference method for GFR estimation, is impractical for routine use in these patients, and Cr-51-EDTA measurements of the GFR have been rarely reported in this disease. Methods In order to obtain reference Cr-51-EDTA values in this disease, we studied 70 patients (40 females; 13-59 years of age, mean: 31.6 years) with homozygous SCA, normal serum creatinine and urinary albumin excretion 50 years). Results The mean GFR (+/- standard deviation) obtained for the 70 patients was 111.5 +/- 23.1 ml.min(-1). Analysis of variance for evaluation of the possible interaction effect between Cr-51-EDTA clearance and sex, age, urinary albumin and haematocrit demonstrated patient age as the only factor influencing Cr-51-EDTA clearance (P<0.001). The Spearman correlation coefficient showed a significant relationship between Cr-51-EDTA clearance and patient age (r= - 0.44, P= 0.0001), but not between Cr-51-EDTA and urinary albumin (r= - 0.17, P= 0.1546) or haematocrit (r=0.079, P=0.5121). The group aged 20-29 years presented the highest Cr-51-EDTA clearance mean value (126.7 +/- 20.4 ml.min(-1)), with a progressive reduction in the older groups. Conclusion Young adults with homozygous SCA, normal serum creatinine and micro-albuminuria or normo-albuminuria present supranormal Cr-51-EDTA GFR values. These values rapidly decrease after 30 years of age. We did not find association between urinary albumin and GFR in these patients.271295996
High pre-therapy [Tc-99m]pertechnetate thyroid uptake, thyroid size and thyrostatic drugs: predictive factors of failure in [I-131]iodide therapy in Graves' disease
Background and objective Several factors may interfere with the success rate of radioiodine therapy (RIT) in Graves' disease. Our aim was to evaluate, retrospectively, some of these factors in the outcome of RIT. Methods Patient gender, age at diagnosis, ophthalmopathy, disease duration, thyroid size, drug used as clinical treatment, thionamide withdrawal period during RIT preparation, FT4, TSH and [Tc-99m]pertechnetate thyroid uptake prior to RIT were studied as potential interference factors for RIT success. Eighty-two Graves' disease patients were submitted to RIT after thionamide treatment failure. Prior to RIT, 67 patients were receiving methimazole and 15 propylthiouracil. Thirty-three patients received thionamides during RIT; in 49 patients the medication was withdrawn for 2-30 days. [Tc-99m]pertechnetate thyroid uptake was determined before RIT. Fixed doses of 370 MBq of [I-131]iodide were administered to all patients. Results Eleven patients became euthyroid; 40 became hypothyroid and 31 remained hyperthyroid. There was no association between outcome and age at diagnosis, gender, ophthalmopathy, pre-RIT FT4, TSH, antithyroid antibodies or thyrostatic drug. Multiple logistic regression showed higher probability of treatment success in patients with thyroid mass < 53 g (odds ratio (OR) = 8.9), with pre-RIT thyroid uptake < 12.5% (OR=4.1) and in patients who withdrew thionamide before RIT (OR=4.9). Conclusions Fixed doses of 370 MBq of radioiodine seem to be practical and effective for treating Graves' disease patients with [Tc-99m]pertechnetate uptake < 12.5% and thyroid mass < 53 g. This treatment is clearly not recommended for patients with large goitre. In contrast to what could be expected, patients with a high pre-RIT thyroid uptake presented a higher rate of RIT failure.261195796